Solar Radiator

ABSTRACT

A solar radiator comprising at least one panel ( 2 ) composed of a device which in turn is composed of one ( 30 ) or two heat-conducting laminas ( 31, 32 ), the solar radiator being adapted to produce a protective shade and being adapted to receive, transmit and dissipate passively, without causing pollution or using other power, at least part of the energy of the solar radiation that strikes it. The solar radiator is designed to protect the soil, crops and plants against excessive solar radiation.

TECHNICAL FIELD

The present invention relates to a solar radiator suitable to collect,transmit and dissipate at least partially the energy of the solarradiation that strikes it, so as to control at least partially theeffects of excessive solar irradiation and protect portions of soilrelated to areas at risk of drought or desertification, and alsosuitable to protect areas at risk of thawing of snow or glaciers andmore.

BACKGROUND ART

As is known, the conditions of the atmosphere and life on Earth dependcritically on the amount of irradiation received from the sun. Solarradiation is transmitted by irradiation, which occurs by means ofelectromagnetic waves which penetrate easily to the innermost layers ofthe atmosphere. This application of energy helps to determine thecharacteristics of the climates on Earth and in particular evendifferences in temperature of a few degrees Celsius have a great effecton climate.

This amount of heat sometimes reaches values which not only affectconsiderably the environmental and climatic conditions but eveninterfere directly with plant and animal life and with human activitiesconnected to it, for example agricultural activities in dry ordesert-like regions.

In the building sector, in order to deal with the excessive amount ofheat sometimes transmitted to buildings and structures, an attempt hasbeen made over time to devise various insulation systems, the mosteffective of which are based on building ventilated roofs and walls.According to this constructive solution, the primary walls that actuallyconstitute the buildings and coverings receive the superimposed additionof other walls, which are arranged further outward and are separated soas to form air spaces which dissipate at least partly the heat generatedby solar irradiation, or walls covered with insulating material areused, or sunshades are installed.

Unfortunately, such solutions affect only the building sector, whereaslittle has been done to reduce the effect of excessive solar irradiationon crops and soils in general, in which the greatest effort has been putinto enhancing irrigation systems. However, it should be noted thatirrigation water normally contains a certain quantity of salts, whichover time tend to accumulate in the soil and become toxic for plants;therefore, it would be convenient to avoid the abuse of irrigationwater, at least in order to slow the accumulation of these salts in thesoil.

DISCLOSURE OF THE INVENTION

The aim of the present invention is to solve at least partially theproblems described above, by providing a solar radiator which, despiteworking passively, is capable of reducing the effects caused byexcessive exposure of soils to the rays of the sun and of modifyingaccordingly the irradiation conditions, reducing their effects andmaking the areas protected by solar radiators more suitable for thespontaneous growth of plants and more.

Within this aim, an object of the invention is to provide a solarradiator which is more or less complex and is capable of reducing atleast partially the effects of solar irradiation in order to prevent theexcessive heating of portions of the soil and of the first meters of airrelated to said soil, contrasting the thawing of snow and ice inmountain or polar regions and contrasting, in dry and desert-like areas,the drying of the soil and its gradual desertification.

Another object of the invention is to provide a solar radiator which, insome situations, is capable of facilitating agricultural activities evenin dry or desert-like areas.

Another object of the invention is to provide a solar radiator which isable to reduce the effects caused by periods of drought withoutconsuming energy.

Another object of the invention is to provide a solar radiator which iscapable of keeping in the shade or partial shade for many hours of theday important portions of the site where it is installed, reducing theevaporation of the water or moisture contained in the soil andconsequently contrasting its drying, facilitating the development ofplants and facilitating agricultural activities.

Another object of the invention is to provide a solar radiator which iscapable of applying a protective action against at least part of theharmful effects caused by the wind.

Another object of the invention is to provide a solar radiator which canbe manufactured with materials which can be recycled and is advantageousalso from an environmental standpoint.

This aim and these and other objects which will become better apparenthereinafter are achieved by a solar radiator, characterized in that itcomprises at least one panel, which in turn is composed of a devicewhich is normally composed of two heat-conducting laminas, said panelbeing adapted to collect, transmit and disperse passively at least partof the energy of the solar radiation that strikes it.

BRIEF DESCRIPTION OF THE DRAWINGS

Further characteristics and advantages of the invention will becomebetter apparent from the following detailed description of somepreferred but non-limiting and not exclusive embodiments of a solarradiator according to the invention, illustrated by way of non-limitingexample in the accompanying drawings, wherein:

FIG. 1 is a perspective view of a panel of the invention in a firstembodiment;

FIG. 2 is a partially sectional enlarged-scale side view of a portion ofthe panel of FIG. 1;

FIG. 3 is a sectional view of another embodiment of the device of FIG.2;

FIG. 4 is a perspective view of a possible variation of theheat-conducting laminas;

FIG. 5 is a perspective view of a solar radiator according to theinvention in various embodiments;

FIG. 6 is a plan view of a first embodiment of a solar radiator, inwhich the segments indicated by the arrows 2 schematically represent thepanels;

FIG. 7 is a plan view of a second embodiment of a solar radiatoraccording to the invention;

FIG. 8 is a plan view of a third embodiment of a solar radiatoraccording to the invention;

FIG. 9 is a plan view of a fourth embodiment of a solar radiatoraccording to the invention;

FIG. 10 is a perspective view of another embodiment of a heat-conductinglamina of a panel according to the invention;

FIG. 11 is a front view of an example of use of a solar radiatoraccording to the invention;

FIG. 12 is a front view of another embodiment of a panel of a solarradiator according to the invention during production;

FIG. 13 is a front view of the embodiment of FIG. 12 upon completion;

FIG. 14 is a plan view of another embodiment of the panel of FIG. 1;

FIG. 15 is a plan view of a variation of the embodiment of FIG. 14;

FIG. 16 is a plan view of another variation of the embodiment of FIG.15;

FIG. 17 is another embodiment of the panel according to the invention;

FIG. 18 is a view of a panel with a device with one heat-conductinglamina;

FIG. 19 is a partial lateral enlarged-scale sectional view of theembodiment of FIG. 18 of the device with a single lamina;

FIG. 20 is an enlarged-scale sectional side view of a variation of thedevice of FIG. 19;

FIG. 21 is a view of a panel composed of a device constituted by afabric made of heat-conducting material;

FIG. 22 is a view of an alternative embodiment of the panel of FIG. 21.

WAYS OF CARRYING OUT THE INVENTION

With reference to the figures, a solar radiator, generally designated bythe reference numeral 1, comprises, according to the invention, at leastone panel 2, which is designed to: a) produce shade; b) collect part ofthe energy irradiated by the sun toward the ground to be protected; c)generate rising air streams; d) dissipate passively into the atmosphereat least said energy without using additional energy.

The panel according to FIG. 1 entails fixing the device, which iscomposed of two heat-conducting laminas 31 and 32 which are arrangedvertically so as to substantially face each other and are spaced by twolateral spacers 41 and 42, which are interposed between the twoheat-conducting laminas 31 and 32 and are joined at their lateral endsin order to form an interspace 50, so that they are rigidly coupled to asupporting frame, which by way of example shown in FIG. 1 is constitutedby a simple pair of poles 81 and 82, which are driven at right anglesinto the ground and which, by supporting said laminas vertically, notonly determine a distance thereof from the ground which allows access ofthe air into the interspace 50 but also fixes their direction withrespect to the path of the apparent daily motion of the sun or accordingto another more convenient orientation.

In particular, the two heat-conducting laminas 31 and 32, which can beconstituted for example by thin laminas made of metal or associatedalloys or can be made of other heat-conducting materials suitable forthe purpose to be achieved, have shapes which are not necessarilyregular but substantially mutually coincident, while their dimensionsand thickness may vary within such limits as to ensure the mechanicalstability of the panel 2, allowing said panel to withstand for examplethe stresses due to atmospheric agents, such as for example the wind.

FIG. 2 illustrates the effects of the operation of the solar radiatorapplied to a panel with a device composed of two heat-conductinglaminas, wherein the arrows inside the laminas 31 and 32 represent therising air flow within the interspace 50. The shadow produced by thepanel is shown to the right of the lamina 32. FIG. 2 does not show theflow of rising air to the left of the lamina 31 as it is a secondaryflow which has a lower effect than the flow within the interspace 50.

FIG. 3 is a view of the effects of the operation of the solar radiatorapplied to the panel with a device composed of two heat-conductinglaminas 31 and 32 and a thermally insulating lamina 16 which isinterposed between the two laminas in order to reduce, by contact of theair outside the panel with the lamina 32, the dissipation of the heatenergy of the stream of air that circulates in an interspace 51.

As shown in FIG. 4, the strength of the panel 2 can be increased bylaminas with a reinforcement border 6, which is joined to at least oneportion of the edge of the heat-conducting lamina 30 so as to strengthenits structure, and it can also be strengthened by a mesh 7, which isjoined to at least one portion of the heat-conducting lamina 30, or byan advantageous combination of the two reinforcements.

The mechanical strength of the panel 2 can be increased further by usingheat-conducting laminas 30 with a horizontally corrugated surface, asshown in FIG. 10.

In the embodiment shown in FIGS. 12 and 13, the panel 2 takes the formof a structure composed of poles, cables and hooks and otheraccessories, in which the heat-conducting laminas 31 and 32 can beconstituted by thin laminas of metal or other heat-conducting materials,as described earlier, or by sheets of heat-conducting fabric 121 and122, which are joined at their upper ends to a first pair of overheadcables 13 and at their lower ends to a second pair of overhead cables 14which are connected to a supporting frame 15, which is formed forexample by two poles and the corresponding braces, which supports andstretches them. In the specific case, the sheets of heat-conductingfabric 121 and 122, shown in FIGS. 12 and 13, can incorporate thesupporting frame 15 or might be arranged laterally therein both on thesame side, without incorporating it, by utilizing anchoring elements andspacers which are not shown in the accompanying figures.

In FIGS. 14, 15 and 16, the supports are not shown and might be the samespacers 41 and 42, which are higher than the heat-conducting laminas.

With FIG. 17, as an alternative, it is possible to provide the panel 2by using two heat-conducting laminas 31 and 32 with different heights,ensuring in any case access of the air to the interspace 50, as shown inthe accompanying figure. It is optionally possible to fix to the groundthe heat-conducting lamina with a greater height in order tosubsequently support the other one and constitute a self-supportingstructure.

FIG. 18 is a view of the panel 2 with a device with one heat-conductinglamina 30 and supporting poles 81 and 82.

FIG. 19 illustrates the effects of the operation of a solar radiatorapplied to the panel 2 with one heat-conducting lamina 30, where due tothe lack of the second heat-conducting lamina, the two rising airstreams are practically identical and are shown in FIG. 19 by means ofthe vertical arrows. FIG. 19 does not show the effect of the contact ofthe two rising air streams in contact with the air that surrounds thepanel for the reasons that will be detailed during the explanation ofFIG. 20.

FIG. 20 illustrates the operation of the solar radiator applied to apanel with the device with one heat-conducting lamina 30 and twotransparent laminas 21 and 22. This embodiment allows to concentratealmost all of the energy that is collected by the heat-conducting laminain the two air streams that circulate in the interspaces 51 and 52,increasing considerably the efficiency of the panel 2.

FIG. 21 is a view of a panel composed of a device constituted by afabric made of heat-conducting material. Such fabric is supportedlaterally with respect to the supporting frame by means of cables andcorresponding accessories, the latter not being shown in theaccompanying figures. As an alternative, the fabric can be fixeddirectly to the supporting poles 15 by means of other accessories. Theheat-conducting fabric can be supported by metallic laminas.

FIG. 22 is a view of a panel as in FIG. 21, with the difference that thedevice composed of a heat-conducting sheet or lamina passes alternatelyfrom one side to the other of the poles 15 that support the panel.

The effectiveness of each panel 2 can be increased by means of severalrefinements, the first of which entails using lateral spacers which aretrapezoidal so as to give the interspace 50 a truncated-pyramid shape.The convergence of the heat-conducting laminas 31 and 32 toward theirupper end causes the air that enters from the lower end of theinterspace 50 to be forced, during its rising motion, to strike withgreater pressure the surface of the heat-conducting laminas 31 and 32,facilitating heat exchange considerably.

Additional solutions aimed at adjusting energy absorption by theheat-conducting laminas 31 and 32 cover externally or internally or onboth sides said laminas with a light-absorbing layer, which isconstituted for example by a film or a coat of dark and preferably mattpaint.

Further solutions aimed at improving the solar energy absorption of thepanel entail that the device, composed of the heat-conducting laminasand any spacers, comprises accessories such as horizontal and/orvertical hinges which are connected mechanically to the supporting polesat the convenient center-of-gravity axes, vertical or horizontal centersof gravity or with a universal-joint device, in order to allow to varythe orientation of the device, and consequently of the laminas, as afunction of the variation of the position of the sun during the day. Inorder to further enhance the orientation capacity of said device, thehinges and other accessories mentioned earlier can be provided with aplurality of automated and programmed electromechanical components,which are functionally connected to said orientation means in order toassist said remote orientation.

Protection of each panel 2 against the action of natural electricalagents can be achieved by resorting for example to lightning protectionor by using for example a cathode protection, or both, or anothersolution.

The environmental impact of the solar radiator 1 can be reduced from avisual standpoint by covering each panel 2 with a camouflage coloringwhich resembles the coloring of the surrounding environment, or from anenvironmental standpoint by providing each panel 2 by using recyclablematerials, such as wood poles and metal laminas.

Further embodiments of the panel 2, shown in the accompanying FIGS. 14,15 and 16, entail giving the heat-conducting laminas 31 and 32 anarc-like or even cylindrical shape. In this case, each panel 2 iscomposed of two heat-conducting laminas 31 and 32 which have a differentradius of curvature, are mutually coaxial and are spaced by two lateralspacers 41 and 42 which are interposed between the two heat-conductinglaminas 31 and 32 and are joined at their lateral ends, or indiametrically opposite positions, so as to form internally theinterspace 50, which allows the passage of the air stream generated dueto solar irradiation; the supports are not detailed in the accompanyingfigures. These embodiments, which can be easily installed andsubsequently removed, are for example, thanks to their shape,particularly useful to protect delimited areas in which particular cropsare planted, such as for example young plants, in locations where thereis insufficient water for irrigation and it is not convenient to useother protections. If necessary, it is also possible to arrange theheat-conducting opaque lamina 30 in a substantially horizontal position,keeping it suspended parallel to the ground, with the aid of cables andrespective supports and accessories, providing in the heat-conductinglamina optionally a plurality of through holes in order to allow theoutflow of the hot air that forms below it.

The solar radiator 1, shown generally in FIGS. 6, 7, 8 and 9, comprisesadvantageously a structure constituted by a plurality of panels 2 whosenumber can vary according to the extension of the surface to beprotected. The solar radiator is positioned by arranging the panels 2along substantially parallel rows and by installing them so that theheat-conducting laminas 31 and 32 are arranged at a distance from theground which is variable from a few centimeters to a few meters (wherethe term “variable” does not mean that the laminas move up and down),such as to leave a space sufficient to allow the natural circulation ofthe air within the interspace 50. The rows composed of the panels 2,which are superimposed and arranged side by side so as to constitute asort of long modular panel, must be spaced and oriented so that theirfaces are directed east/west or according to the effect to be obtainedand can be substantially straight or slightly curved as in FIGS. 7 and9. In particular, it is necessary to avoid the mutual influence thatshadows can produce during the hottest hours of the day on the nearbypanels, optionally ignoring their effect in the early and late hours ofthe day.

Considering by way of non-limiting explanatory example the equatorialline and panels with two heat-conducting laminas, the rows composed ofthe panels 2 generally must be positioned so that each panel 2advantageously has its heat-conducting lamina 31 exposed to the east inorder to collect the greatest quantity of solar rays in the morning andthe heat-conducting lamina 32 exposed to the west in order to collectthe greatest quantity of solar radiation in the afternoon, or viceversa. Of course, in the case of a panel with a single heat-conductinglamina, the panels are installed so that the lamina is oriented with oneface to the east and the other face to the west, respectively. Ofcourse, the installation orientation of the panels 2 depends on thegeographical location of the soil to be protected and can vary accordingto the seasons and to the path of the daily apparent motion of the sunor to the result to be obtained.

With reference to FIG. 19, the rays of the sun strike theheat-conducting lamina 30, heating it; the lamina is made of metal orother heat-conducting material or other material suitable for thepurpose. The lamina must be oriented so that its faces collect thegreatest quantity of solar radiation in the morning and afternoon. Therays of the sun produce a considerable heating of the lamina. The laminacools due to the effect of the spontaneous air streams, as shown indetail in FIG. 19. The warm air streams rise due to their lower relativedensity. In this first step of the construction of the panel, one shadowand two warm air streams are obtained as shown in detail in FIG. 19. Theoperating principle entails increasing the efficiency of the panel witha single lamina of heat-conducting material by installing a secondheat-conducting lamina as shown in the details given in FIGS. 1, 2 and17. The interspace 50 allows the circulation of a natural cooling airstream that is delimited to it, said air arriving from the vicinity ofthe panel. The second lamina allows the circulation of the air stream inthe interspace 50, avoiding the dispersion of the heat energy of saidair stream with the rest of the air that circulates in the vicinity ofthe panel. Another possibility to increase the heat efficiency of thepanel entails installing two transparent laminas which are coupled tothe heat-conducting lamina as shown in FIG. 20, said transparent laminasbeing made of the most appropriate material. With this modification, theair streams generated within the interspaces 51 and 52, according toFIG. 20, do not dissipate the heat energy with the air that surroundsthe panel. In this manner, at the output of the two interspaces 51 and52 of the panel, as shown in FIG. 20, it is possible to obtain twostreams of air which is warmer than the air on the edges of the laminaof the panel without transparent laminas. Other solutions to increasethe efficiency of the panels have been described earlier. All the panelsproduce warm air. All the streams of warm air move spontaneously awayfrom the ground, carrying to altitude the heat energy that theyaccumulated while they were in contact with the laminas of the panel.All the warm air streams remove at least partially the excessive heatenergy to disperse it at higher levels of the atmosphere.

In the case of panels with one or two interspaces, the laminas areinstalled at a suitable distance from the ground so as to allow air toenter from the lower part of the interspaces. The heat-conductinglaminas and any accessories may be installed up to more than 1 meterabove the ground depending on the results to be obtained.

While the panel 2 shields the ground from the direct action of the sun,producing shadow zones, the streams of rising warm air, in addition todrawing cooler air indeed from these adjacent shadow zones, disperse inthe atmosphere the heat accumulated by the heat-conducting laminas,moving it away from the ground.

In any case, the solar radiator 1 does not accumulate energy, coolsspontaneously during the night, does not pollute and does not requireadditional energy to operate.

Specific examples of application, implemented to reduce the effects ofthe irradiation of the sun which might be too intense in certainsituations, provide for the installation of the solar radiator 1 on thecovering of greenhouses 150, as shown in FIG. 11, or on snowfields orice-covered surfaces, so as to prevent or delay their melting.

If the effects of the solar radiator 1 are not considered necessary orare considered excessive, it is possible to remove the radiatorcompletely and at any time, or optionally cover it with sheets or otherlight-reflective material, so as to neutralize its effects, or simplyroll up the heat-conducting laminas 31 and 32 of the panels 2 if theyare constituted by sheets or other flexible material or neutralize theireffect with other compatible systems.

In practice it has been found that the solar radiator according to theinvention fully achieves the intended aim and objects, since althoughbeing simple and relatively cheap to provide it ensures the possibilityto reduce the effects of an excessive exposure of soil to solarradiation and to modify environmental conditions, lowering thetemperature of the portion of ground that is protected and of the firstmeters of the atmosphere that are adjacent to it, consequently reducingthe melting of snow and ice in mountain or polar areas and in some casessupplying moisture, especially at night, due to the condensation of themoisture in the air, as is very likely for example in dry anddesert-like areas.

Further, the solar radiator according to the invention is able to reducethe effects of periods of drought without consuming energy and iscapable of keeping in the shade or partial shade for many hoursimportant portions of the location where it is installed, reducing theevaporation of water, reducing the dehydration stress of plants, orreducing the evaporation of ground moisture, and consequentlycontrasting the drying of the ground.

The solar radiator thus conceived is susceptible of numerousmodifications and variations, all of which are within the scope of theappended claims; all the details may further be replaced with othertechnically equivalent elements.

In practice, the materials employed, so long as they are compatible withthe specific use, as well as the contingent shapes and dimensions, maybe any according to requirements and to the state of the art.

The disclosures in Italian Patent Applications No. VI2005A000269 and No.VI2005A000293 from which this application claims priority areincorporated herein by reference.

1. A solar radiator, characterized in that it comprises at least onepanel (2), which comprises at least one pair of supporting poles (81,82) and a device composed of two heat-conducting laminas (31, 32) whichmay even have mutually dissimilar shapes and are substantially verticaland face each other and are mutually spaced by at least one pair oflateral spacers (41, 42), which are interposed between saidheat-conducting laminas and are joined at their lateral ends so as toform an interspace (50) between said two heat-conducting laminas, saidpanel (2) being adapted to produce shade and collect, transmit anddisperse passively at least part of the energy of the solar radiationthat strikes it.
 2. A solar radiator, characterized in that it comprisesat least one panel (2) which comprises a supporting frame and a devicecomposed of a heat-conducting lamina (30), said heat-conducting laminabeing joined to said supporting frame, said solar radiator being adaptedto produce shade and collect, transmit and disperse passively at leastpart of the solar energy that strikes it.
 3. The solar radiatoraccording to claim 1, characterized in that said heat-conducting laminas(31, 32) have different heights, the tallest of said two heat-conductinglaminas acting as ground support in order to help to support said panel(2) and ensure the access of said air into said interspace.
 4. The solarradiator according to one or more of the preceding claims, characterizedin that said lateral spacers (41, 42) are substantially trapezoidal andgive said interspace (50) a substantially truncated-pyramid shape. 5.The solar radiator according to one or more of the preceding claims,characterized in that said panel (2) comprises at least one transparentlamina, whose shape substantially coincides with the shape of saidheat-conducting lamina, said transparent lamina facing saidheat-conducting lamina at a distance which is determined by at least onepair of lateral spacers (41, 42) which are interposed between saidtransparent lamina and said heat-conducting lamina and are joined attheir lateral ends in order to form an interspace (50) between saidtransparent lamina and said heat-conducting lamina.
 6. The solarradiator according to one or more of the preceding claims, characterizedin that said panel comprises a thermally insulating lamina (16), whoseshape substantially coincides with the shape of said heat-conductinglaminas (31, 32) and which is interposed between said heat-conductinglaminas (31, 32) in order to form two interspaces (51, 52) of equalsize.
 7. The solar radiator according to one or more of the precedingclaims, characterized in that said panel (2) comprises a camouflagecoloring which reproduces the landscape in order to reduce the visualenvironmental impact.
 8. The solar radiator according to one or more ofthe preceding claims, characterized in that said panel (2) comprises aprotection against electrical phenomena.
 9. The solar radiator accordingto one or more of the preceding claims, characterized in that said panel(2) comprises a structure which is composed of poles, cables andaccessories and supports vertically at least one heat-conductingelement.
 10. The solar radiator according to one or more of thepreceding claims, characterized in that it uses devices composed ofmaterials which are different from the laminas of heat-conductingmaterial.
 11. The solar radiator according to one or more of thepreceding claims, characterized in that it comprises accessories whichallow to roll up the laminas or roll-up fabrics.
 12. The solar radiatoraccording to one or more of the preceding claims, characterized in thatit comprises at least one heat-conducting lamina with at least one typeof mechanical reinforcement for at least one portion of saidheat-conducting lamina in order to give mechanical stability to saidpanel.
 13. The solar radiator according to one or more of the precedingclaims, characterized in that said heat-conducting laminas comprise alight-absorbing layer, which is superimposed on at least one portion ofsaid heat-conducting laminas in order to increase the effectiveness ofsaid panel.
 14. The solar radiator according to one or more of thepreceding claims, characterized in that said heat-conducting laminas(31, 32) comprise a curve which gives said panel an arc-likeconfiguration.
 15. The solar radiator according to one or more of thepreceding claims, characterized in that said heat-conducting laminas aresubstantially cylindrical and are arranged mutually coaxially with theaid of spacers which act as supports, allowing the free circulation ofair that enters from the lower part of the interspace of the panel. 16.The solar radiator according to one or more of the preceding claims,characterized in that it comprises a plurality of panels (2).